Abstract: A mail traying apparatus which trays or sweeps mail envelopes, which are positioned in a mail stacker bin, into a mail tray and to deliver the same to an outbound conveyor or cart. The apparatus includes a robot having a robot arm mounted thereon with the robot arm having a mail tray support at the tool end thereof. The robot moves the robot arm to a source of empty mail trays so that an empty mail tray may be positioned in the mail tray support. The robot then moves the empty tray to the discharge end of the mail stacker bin, sweeps the mail into the mail tray, and then moves the filled mail tray to an outbound conveyor or cart.